I once measured at 1.8 ! I was shaking so much I could hardly use the meter. Massive headache, dizzy, fear of imminent death. Then with the rebound (after consuming too much glucose in the panic) I felt almost as bad. It seems to also have to do with how fast I am falling and so sometimes have felt hypo in the 5s. I have some fruit whenever I feel low now, like half an apple, wait quietly and in about 15 minutes I feel my energy is ok again without spiking. The carbs I eat are mostly above-ground vegetables, limited carrots and fruit sparingly. (I also eat protein and lots of fat.) For me a key is eating the same amount of carbs every day and at the same times (approx) and for weeks now I have stayed in the normal range.